Multiple-unit mail boxes, also known as neighborhood delivery and collection box units or cluster boxes, are often installed in new housing developments. The U.S. Postal Service typically prefers cluster boxes because they allow mail for a number of homes to be delivered to a central point, saving time, fuel and money.
Recently, the U.S. Postal Service has become the dominant buyer of such multiple-unit mail boxes. One result of this is that prices of such multiple-unit box units have been drastically reduced. The manufacturing cost of such conventional multiple-unit mail boxes has left little room for profit. Consequently, there is a need to produce a cost-effective multiple-unit mail box, while at the same time retaining and even enhancing such desirable qualities as: high-strength, cosmetically appealing, security and resistant to various weather conditions.
Prior art patents disclose various construction of multiple-unit mail boxes. For example, U.S. Pat. No. 1,817,191 to Harmony discloses a mail box station having individual boxes interchangeably fitted in the compartments of the mail box station.
U.S. Pat. No. 3,081,023 to Taylor discloses an assembly of rural mail boxes which are adapted for connection with similar mail boxes so that a group of the mail boxes may be established at one particular location. Each mail box is formed from one continuous piece of metal such as aluminum as some other light and non-corrosive metal.
U.S. Pat. No. 4,121,758 to Bonner discloses a gang-type mail box having a number of compartments each having a liner with a metal slide. Other patents of lesser relevance to the present invention include U.S. Pat. Nos. 1,612,335; 1,709,363; 1,719,541; 1,735,379; 1,747,003; 4,148,432 and 4,247,039.